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A comment on International Space Station 437.800 MHz cross band FM repeater activated.

Re:International Space Station 437.800 MHz cross band FM rep... by sizzzzlerz on Monday September 07, 2020 @09:52AM (#24399413)
A sat tracking program I have shows ISS passing almost directly overhead in about 40 minutes. How would the downlink frequency vary due to doppler shift as it transits from local horizon to local horizon?
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Re:International Space Station 437.800 MHz cross band FM rep... by oliveshell on Monday September 07, 2020 @10:19AM (#24399570)
Good question. Some info on tuning for Doppler shift:

https://www.qsl.net/ah6rh/am-radio/spacecomm/doppler-and-the...

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Re:International Space Station 437.800 MHz cross band FM rep... by sizzzzlerz on Monday September 07, 2020 @12:02PM (#24400323)
Thank you, that was very informative. Seems like the calculations are pretty straight forward. I need to see if I can create my own charts like that.
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Re:International Space Station 437.800 MHz cross band FM rep... by nickysielicki on Monday September 07, 2020 @03:22PM (#24401910)
The open source software gpredict can do this live for you.
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Re:International Space Station 437.800 MHz cross band FM rep... by tomfanning on Monday September 07, 2020 @10:48AM (#24399764)
Short answer - by one or two of the smallest steps on a typical handheld, starting above the nominal frequency and ending below it. A bit more than that for UHF downlinks.
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